1. Field of the Invention
The present invention relates to N-halothio-sulfonamide-modified rubber products, particularly butyl rubber, and a process for their preparation.
2. Description of Information Disclosures
Butyl rubber is a well known product.
U.S. Pat. No. 3,915,907 (R. J. Hopper), U.S. Pat. No. 3,970,133 (R. J. Hopper), and U.S. Pat. No. 4,820,780 (R. J. Hopper), the teachings of which are hereby incorporated by reference, disclose chlorothiosulfonamide-modified terpolymers of ethylene, an alpha olefin and a nonconjugated diene. The desirability and advantages of these modified terpolymers were also disclosed in articles authored and co-authored by R. J. Hopper (Rubber Chemistry and Technology, vol. 49, pages 341-352, 1976) and International Conference on Advances in Stabilization and Controlled Degradation of Polymer, Lucerne, Switzerland, May 23-25, 1984).
It has now been found that the reaction of N-halothiosulfonamide with a rubber will produce N-halothio-sulfonamide-modified rubber reaction products having improved properties.
Butyl rubber has many known desirable characteristics such as, for example, resistance to chemical attack, ozone resistance, electrical insulation capability. Improvement of the physical and dynamic properties of butyl rubber are still sought and are of practical importance. Butyl rubber does not easily form cocurable compositions with high diene rubbers such as natural rubber, styrene-butadiene rubber and the like. The modified rubber of the present invention is more readily curable with high diene content rubbers and, therefore, permits obtaining cured compositions which have the desirable characteristics of butyl rubber as well as the desirable characteristics of high diene content rubbers.